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Biomedical subjects

N Yoshioka

Publications and source records attributed to N Yoshioka.

At least 91 records · Page 5Linked to original sources
PubMed1995

TRH stimulation test in healthy elderly: paradoxical response of growth hormone is abnormal in normal aging.

The purpose of this study was to measure TSH (thyrotropin), PRL (prolactin) and GH (growth hormone) response to a TRH (thyrotropin releasing hormone) stimulation test in 37 healthy elderly male subjects and determine if these responses correlate with the incidence of mental decline; and also, to determine if these responses occur more frequently in the elderly than in the general population. A hyperresponse of TSH was documented in 7 of our 37 elderly male subjects, a delayed response of TSH in 4, a low response of PRL in 29 and a significant paradoxical response of GH in 2. Those subjects with a significant paradoxical response of GH were 82 and 83 years of age and their HDS was 20.0 and 25.5, respectively. We did not find a causal relationship between mental decline and the paradoxical response of GH, but our data suggests that the paradoxical response of GH is not normal in elderly older than 80 years old.

Aged↗
PubMed1995

[Role of antigen-antibody reaction in pulmonary hypertensive reaction after antigen challenge].

Pulmonary arterial pressure, airway pressure, and lung weight increase were studied after antigen (human O-N type erythrocytes) challenge in isolated-perfused sensitized rabbit lungs. To investigate whether these hemodynamic changes are mainly caused by antigen-antibody reaction or by the other mechanisms, we measured changes of pulmonary arterial and airway pressures, and lung weight gain after antigen challenge in perfused nonsensitized rabbit lungs. Thirteen nonsensitized rabbits were divided into 2 groups; in N group (n = 5), antigen was given into Krebs Hanseleit perfusate; in Ab group (n = 8), antibody was given into reservoir 30 min prior to antigen challenge. Pulmonary arterial pressure in Ab group was higher than in N group after antigen challenge. Maximal increase in pulmonary arterial pressure after antigen challenge depended on agglutinin titer of antibody in perfusate (delta Ppa = 0.068 x [titer]-0.146, r2 = 0.929). However, there were no significant differences between the two groups in changes of airway pressure and lung weight gain after antigen challenge. Although agglutinin titer of perfusate in Ab group was higher than our previous study, pulmonary hypertensive reaction to antigen in Ab group was significantly lower. It is concluded that the other mechanism besides antigen-antibody reaction itself can be responsible for hemodynamic changes after antigen challenge.

Airway Resistance↗
PubMed1995

[Exposure to blood during midwifery procedures--blood contact events to midwives occurred in a delivery room].

Midwives are often exposed to blood during delivery procedures. A study aimed at clarifying actual status of blood contact during midwifery procedures was performed. Observations in a delivery room were conducted to record blood contact events experienced by midwives from the time of episiotomy until 2 hour after expulsion of the placenta. All gloves used by midwives were collected and tested for holes. Blood contact was defined as any contact with blood of a parturition woman as recognized visually by an observer. During a one-month study period data was obtained from a total of 19 midwives (12 midwives and 7 student midwives) who assisted in 8 deliveries. All of the midwives wore gowns with long sleeves, gloves and caps but did not use eye protection or masks. None of the parturient women had Hepatitis B, Hepatitis C or acquired immunodeficiency syndrome. Deliveries caused widespread blood exposure to the midwives throughout the complete course. Protection from most of this exposure was provided by the gowns and gloves. However, direct blood contacts occurred to the fingers, hands or forearms in several midwives. These events were caused by partly because the midwives unintentionally performed procedures without gloves and partly because blood penetrated the gown and soaked to the skin. Direct blood contacts to the foot in two midwives and to the mouth in one also occurred. The overall perforation rate for gloves examined was 4 out of 154 (2.6%). Two gloves were broken during washing sharp instruments contaminated with blood, one was torn when wearing, and the remaining one appeared to have had a hole prior to use.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

[Prediction of left ventricular functional recovery in patients with acute myocardial infarction using single photon emission computed tomography with thallium-201 and iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid].

The relationships between myocardial perfusion, fatty acid metabolism, and cardiac function were investigated using dual single photon emission computed tomography (SPECT) with thallium and iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid (123I-BMIPP) during the acute (10 +/- 1 days) and recovery (60 +/- 14 days) phases in 29 patients with acute myocardial infarction. There were 18 patients who underwent successful primary coronary angioplasty (PTCA group) and 11 patients who received conservative therapy (non PTCA group). Thallium and BMIPP uptakes were scored visually by a 4-point system and left ventricular ejection fraction (LVEF) was calculated by radionuclide ventriculography. Although significant positive correlations between thallium and 123I-BMIPP scores were observed during both phases, BMIPP scores were significantly lower than thallium scores in both acute and recovery phases in the PTCA group. No significant difference in thallium and 123I-BMIPP scores was observed at the recovery phase in the non PTCA group. LVEF significantly correlated with thallium and 123I-BMIPP scores in both phases in the PTCA group. Furthermore, the difference between thallium and 123I-BMIPP scores during the acute phase significantly correlated with the improvement of LVEF during the follow-up period in the PTCA group (y = 0.92x-0.77, r = 0.65, p < 0.005). These findings suggest that mismatch of perfusion and metabolism in infarcted myocardium assessed by thallium and 123I-BMIPP SPECT is increased by reperfusion therapy and persists at least until the recovery phase of myocardial infarction. The recovery of left ventricular function depends on the extent of the mismatched uptake, indicating a predictor for functional recovery following acute myocardial infarction.

Adult↗
PubMed1995

[Effects of thromboxane A2 receptor antagonist, KT2-962 on pulmonary hypertensive responses to antigen challenge in isolated sensitized rabbit lung].

We investigated whether KT2-962 (thromboxane H2/A2 receptor antagonist) could attenuate increases in pulmonary arterial and airway pressures after antigen challenge in isolated-perfused sensitized rabbit lungs. Sensitized rabbits were immunized intravenously with human O-N type erythrocytes until the agglutination titer against antigen reached above 1:10,000. Nineteen rabbits were divided into three groups. In N group (n = 9), antigen was challenged into perfusate. In KT2 group (n = 5), 1 mg.kg-1 of KT2-962 was given into reservoir 10 min prior to antigen challenge. In Indo group (n = 5), 5 mg.kg-1 of indomethacin was given into reservoir 20 min prior to antigen challenge. Maximal increase in pulmonary arterial pressure after antigen challenge in N group was significantly higher than that in KT2 group or in Indo group (13.4 +/- 3.3 mmHg, 1.5 +/- 0.5mmHg, 1.5 +/- 0.2mmHg, respectively). Maximal increase in airway pressure in N group was higher than that in KT2 group or in Indo group (2.9 +/- 0.8cmH2O, 0.8 +/- 0.2cmH2O, 0.5 +/- 0.2cmH2O, respectively), but this was not significant. Pharmacological potential of KT2-962 to attenuate pulmonary hypertensive responses was estimated 50 times stronger than that of indomethacin. In conclusion, KT2-962 can exert therapeutic effect on pulmonary hypertensive responses induced by immunological reactions.

Animals↗
PubMed1995

Duodenal carcinoid tumor: endosonographic imaging and endoscopic resection.

A 75-yr-old Japanese woman was shown by endoscopy to have a sessile polyp in the duodenal bulb. Endoscopic biopsy confirmed the diagnosis of carcinoid tumor. The endoscopic ultrasound probe showed a 6-mm hypoechoic tumor that was confined to the submucosal layer; the underlying muscularis propria layer was intact. On the basis of these findings, endoscopic resection was chosen, and the tumor was completely resected by the strip biopsy technique with prior hypertonic saline and epinephrine injection; there were no complications.

Aged↗
PubMed1995

[Pulmonary hypertensive responses to erythrocytes components in sensitized rabbits].

Antigen erythrocytes cause a transient pulmonary hypertension in sensitized rabbits. We investigated the main responsible component in the antigen erythrocytes. Eleven rabbits were immunized intravenously with human O-N type erythrocytes every ten days until the agglutinin titer = 1:8,000 was obtained. Another ten rabbits without immunization served as a control group. Human erythrocytes were osmolitically hemolyzed and then separated into hemoglobin and membrane components by centrifugation. In sensitized rabbits, a bolus injection of human hemoglobin 0.7 ml.kg-1 caused increases in pulmonary arterial and airway pressures within 3-4 min. Increase in pulmonary arterial pressure after injection of hemoglobin component was significantly higher than that after injection of membrane component in sensitized rabbits. However, in nonsensitized rabbits both components were ineffective. Leukocytes counts decreased by 73-62% in sensitized rabbit, while they decreased by 16-37% in nonsensitized rabbits 5 min after injection of hemoglobin or membrane component. Platelets decreased by 54-61% in sensitized rabbits, while they decreased by 24-9% in nonsensitized rabbits 5 min after injection of hemoglobin or membrane component. We conclude that hemoglobin is the responsible component in the antigen erythrocytes and chemical mediators, such as thromboxane and platelet activating factor, may not be released from platelets and leukocytes.

Airway Resistance↗
PubMed1995

[Exposure to blood during midwifery operations--a questionnaire study].

A self-administered questionnaire was mailed to all midwives working in Nara Prefecture to investigate blood exposure events at delivery and to consider protective measures for the exposure. Out of the 203 midwives 193 responded to the questionnaire. The median number of deliveries in which the midwives had assisted within the past one year was 35 after excluding those who had not assisted in deliveries at all. The incidence of needle-stick injuries was estimated to be 86.2 per 100 persons within the past one year. The occurrence in the subgroup who had worked as midwife for less than 5 years was 2-3 times higher than that in those who worked for more than 5 years. Over 90% of the midwives had experiences of direct blood contact events to the skin while assisting in their 10 most recent deliveries. Blood contact events occurred in the finger-hand-arm area in 85% of the midwives, on the legs in 62%, in the face in 20% and in the eyes in 1%. Around 20% of the midwives had unintentionally sucked amniotic fluid when using a tracheal catheter on a newborn. The most common occasion where direct blood contact events occurred was while bathing an infant for removing blood and amniotic fluid. The midwives wore a disposal gown more often when assisting in labors of parturient women infected with blood-born infectious diseases than without the diseases, and similarly for wearing gloves when measuring blood loss and for usage of a mechanical device for sucking amniotic fluid in the tracheae of an infant. Based on the results obtained in this questionnaire study and our previous study about blood contact events observed in a delivery room, protective measures for midwives against exposure to blood at delivery are required and some ideas are presented.

Accidents, Occupational↗
PubMed1995

[Usefulness of Doppler ultrasound in predicting the effect of gonadotropin-releasing hormone agonist (GnRHa) on myoma uteri].

This paper shows the value of Doppler ultrasound of the uterine blood flow in predicting the effect of GnRHa on myoma uteri. Thirty-eight patients with myoma uteri were divided into two groups by Doppler ultrasound before treatment: a group with positive arterial blood flow in or around the myoma nodule, and another group with negative arterial blood flow. Histological examinations which were performed in thirty patients demonstrated that the myoma in the negative blood flow group showed higher hyalinization with poor vascularization. In fifteen patients treated with GnRHa (Buserelin 900 micrograms/day), a significant increase (p < 0.01) in the resistance index of the uterine arteries was induced and suppressed the serum estradiol concentration in all cases during GnRHa therapy. The size of the myoma nodules also decreased in all 6 patients in the positive blood flow group, but in only 3 of the 9 patients in the negative blood flow group during GnRHa therapy. These results indicated that Doppler assessments of the arterial blood flow in myoma would be useful in predicting the effect of GnRHa on myoma uteri.

Adult↗
PubMed1995

Fifteen-year statistics and observation of facial bone fracture.

During the past 15 years, we encountered 1051 facial fractures. The number of patients with facial fractures accounted for 0.76% of the over all outpatients at the ENT clinic of Osaka City University Hospital. There were 496 nasal bone fractures, 111 maxillary fractures, 167 zygomatic fractures, 122 mandibular fractures, and 130 orbital fractures. These types of fractures accounted for 47.2%, 10.6%, 15.9%, 11.6%, and 12.4% of the over or facial fractures, respectively. The ratio of men to women was nearly three to one, with 794 men and 257 women. Among nasal fractures, injury causes were ranked in the order of fighting, sports, and traffic accident. Among facial fractures, injury causes were ranked in the order of the traffic accident, fighting, and falling down.

Adolescent↗
PubMed1994

Axons regenerate with correct specificity in horizontal slice culture of the postnatal rat entorhino-hippocampal system.

We have used slice culture of the entorhino-hippocampal system to investigate (1) whether nerve fibres which are cut postnatally are able to regenerate and (2) whether the regenerating fibres are able to establish correct selective target specificity in the formation of their terminal fields. Slices of tissue were taken in the horizontal plane through the caudo-ventral pole of the cerebral hemisphere of 9- to 10-day-old rats. Such slices maintain the entorhinal cortex in continuity with the hippocampus and intervening retrohippocampal areas. However, because of the dorsal inclination of the entorhino-hippocampal projection fibres in situ, the segments of the entorhinal cortex and hippocampus contained within each individual horizontal slice were disconnected from each other. During subsequent culture, the formation of fibre connections between the entorhinal area and the hippocampal complex was studied by the extracellular and intracellular anterograde transport of biocytin or biotin dextran, the retrograde transport of biotin dextran or carbocyanine dyes, and by electrical stimulation and recording. For the first 24 h after taking the slice, there were no entorhinal projections beyond the deep white matter, and no fibres reached the hippocampus or dentate gyrus. After 3 days in culture a small number of growing fibres had perforated the subiculum and entered the target areas. Between 6 and 14 days these projections increased and matured. As in the normal adult brain, entorhinal layer II stellate cells projected correctly to the dentate gyrus and hippocampal field CA3, whereas layer III pyramidal cells projected to hippocampal field CA1 and the subiculum. The new fibres grew along both alvear and perforant pathways. Anterograde and retrograde labelling showed that the reciprocal projections from the pyramidal cells of the subiculum and CA1 to the entorhinal area had also been severed at the time of taking the slices, and had similarly regenerated. Our results demonstrate that by taking tissue slices in appropriate planes it is possible to study the regeneration of axons in the tissue environment through which they normally run. This approach avoids the use of coculture and the concomitant difficulties associated with the need for fibres to cross a coculture interface. In horizontal slices of postnatal tissue, severed fibre projections between the entorhinal cortex and the hippocampal complex can regenerate in both directions and re-establish their correct laminar, pathway and target specificity.

Animals↗
PubMed1994

[Serial CT during arterial portography and arteriography of the liver with a triple-lumen balloon catheter].

Serial computed tomography during arterial portography (CTP) and CT during arteriography (CTA) of the liver could be performed on nine of ten patients with hepatocellular carcinoma, using triple-lumen balloon catheters (3-B-C). The 3-B-C was inserted into the common hepatic artery, and the balloon was inflated. We have injected contrast medium into the splenic artery through the side hole of the 3-B-C to perform CTP, and then into the common hepatic artery through the tip hole to perform CTA.

Adult↗
PubMed1994

[Antigen-induced pulmonary arterial responses in the isolated perfused lung of sensitized rabbits].

To investigate whether blood components, such as complements, antibody, platelets and leukocytes, can play important roles in increasing pulmonary arterial and airway pressures after antigen challenge in sensitized rabbits, we measured the time course of pulmonary arterial pressure, airway pressure and lung weight gain after antigen challenge in isolated perfused rabbit lungs. Nineteen rabbits were divided into 3 groups; S group (n = 9), which was sensitized rabbit lung with antigen added into perfusate; NS group (n = 5), which was nonsensitized rabbit lung with antigen added into perfusate; S+R group (n = 5), which was sensitized rabbit lung with autologous erythrocytes added into perfusate. Although agglutinin titer in sensitized rabbits was more than 1: 10,000, that in the perfusate was less than 1:16. Pulmonary arterial and airway pressures significantly increased after antigen challenge in S group, while those in NS and S+R groups did not show any change. Also there were no significant changes in pulmonary arterial and airway pressures and lung weight gain in nonsensitized rabbit lungs of the same agglutinin titer as S group. Lung weight gain in S group was 2-4 times higher than that in S+R group after antigen challenge. We conclude that blood components, such as complements, antibody, platelets and leukocytes, do not play important roles on antigen induced pulmonary responses in sensitized rabbit lungs.

Airway Resistance↗
PubMed1992

Hypocalcemic cardiomyopathy in a patient with idiopathic hypoparathyroidism.

An idiopathic hypoparathyroidism-induced cardiomyopathy patient had severe long-lasting hypocalcemia. The dramatic improvement of cardiac function with correction of only the serum calcium concentration could be quantitatively demonstrated on both echocardiogram and ventriculogram. The concentration of the extracellular calcium ion was considered to have a direct effect on the strength of the myocardial contraction through excitation-contraction coupling. Furthermore, elevated serum creatine phosphokinase and lactate dehydrogenase levels which were thought to be delivered from skeletal muscle returned to the normal range concomitant with the correction of hypocalcemia. The serum calcium concentration and these enzyme level showed significant inverse correlations.

Cardiomyopathies↗
PubMed1991

Anteriorly based pericranial flap: an anatomic study of feeding arteries.

The purpose of this study was to obtain anatomic data on the branching levels of the deep branches of the supraorbital artery (SoA) and of the supratrochlear artery (StA) in pericranial flaps. Ten preserved cadavers were used for this study. Each vessel was identified on 12 sides. The deep branch of the SoA had a larger caliber than that of the StA in seven of nine sides. The branching level of the deep branch of the SoA was cephalad to that of the StA on six of nine sides. The deep branch of the SoA diverged shortly after emerging from the supraorbital foramen or notch. However, there were a few cases in which the branch originated at a distance of a few millimeters before or after the foramen or notch. From a practical standpoint, dissection of this pericranial flap below the level of the supraorbital ridge is not advised, and preservation of both feeding arteries is encouraged in order to establish abundant vascularity for this flap.

Journal Article↗
PubMed1991

The role of cerebellar flocculus in adaptive gain control of ocular reflexes.

Sustained oscillation of the head of an alert animal with inphase or outphase combination of screen oscillation in the horizontal plane induced marked adaptive changes in the gain of the horizontal vestibulo-ocular reflex (HVOR). These changes are assumed to be a prototype of motor learning by the cerebellar flocculus. Several lines of experimental evidence, using rabbits or monkeys as experimental material, have consistently suggested that the plastic changes of neuronal activities of a particular group of floccular Purkinje cells (H-cells) are the sources of the HVOR adaptation.

Adaptation, Physiological↗